From fb2569461182d62d297a69b1388c8328b9a56932 Mon Sep 17 00:00:00 2001
From: Isaac Freund <mail@isaacfreund.com>
Date: Mon, 15 Jun 2026 12:23:40 +0200
Subject: [PATCH] grammar: fix doc comment parsing

/// should not be parsed as a division operator followed by a comment
if it appears in a context where a division operator is accepted.

Add the missing negative lookahead to the SLASH token.
---
 doc/langref/grammar.peg                 | 2 +-
 lib/std/zig/parser_fuzz.zig             | 4 ++++
 lib/std/zig/parser_generated_oracle.zig | 1 +
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/doc/langref/grammar.peg b/doc/langref/grammar.peg
index 5d34b8a4868b52ee0c10bd8862da6a3b83de1d50..46e6859b6fa40ae3e63bc849fabe55d4cd97e02a 100644
--- a/doc/langref/grammar.peg
+++ b/doc/langref/grammar.peg
@@ -537,7 +537,7 @@ RBRACE               <- skip '}'
 RBRACKET             <- skip ']'
 RPAREN               <- skip ')'
 SEMICOLON            <- skip ';'
-SLASH                <- skip '/'      ![=]
+SLASH                <- skip '/'      ![=/]
 SLASHEQUAL           <- skip '/='
 TILDE                <- skip '~'
 
diff --git a/lib/std/zig/parser_fuzz.zig b/lib/std/zig/parser_fuzz.zig
index 32ed24c6afc5d2537f429d1f3709f3f9f6ba3617..6086ed4d319c323c47718ea9a504c6419dae5499 100644
--- a/lib/std/zig/parser_fuzz.zig
+++ b/lib/std/zig/parser_fuzz.zig
@@ -25,6 +25,10 @@ test "operator whitespace" {
         \\}
     );
 }
+// Found using AFL++
+test "doc comment or division operator" {
+    try checkAgainstOracle("0=0///\n0");
+}
 
 fn checkAgainstOracle(source: [:0]const u8) !void {
     var fba_buf: [1 << 18]u8 = undefined;
diff --git a/lib/std/zig/parser_generated_oracle.zig b/lib/std/zig/parser_generated_oracle.zig
index bd7b581760b380e9ed08696a2896093c1bf8fa26..69f23ec3139b3a0da3ff06a82c2b1d910fcf47b4 100644
--- a/lib/std/zig/parser_generated_oracle.zig
+++ b/lib/std/zig/parser_generated_oracle.zig
@@ -3927,6 +3927,7 @@ const Parser = struct {
                 const pos_1 = p.i;
                 const match_1 = (p.i < p.source.len and switch (p.source[p.i]) {
                     '='...'=',
+                    '/'...'/',
                     => blk_2: {
                         p.i += 1;
                         break :blk_2 true;
-- 
2.54.0